Sheet folder



Dec. 27, 1966 R. L. SJOSTRGM 3,294,395

SHEET FOLDER Filed Sept. 18, 1964 4 Sheets-Sheet 1 INVEN'IOR. ROBERT L.sJbsTRoM A ORN EYS Dec. 27, 1966 R. L. SJOST GM 3,294,395

SHEET FOLDER Filed Sept. 18, 1964 4 Sheets-Sheet 2 INVENTOR. ROBERT L.SJifiSTRE'JM ATTORNEYS Dec. 27, 1966 R, L. sJsTRm/l SHEET FOLDER 4Sheets-Sheet 5 Filed Sept. 18, 1964 INVENTOR. ROBERT L. sdsmm M owuATTOR N EYS Dec. 27, 1966 L. sJbSTRM SHEET FOLDER 4 Sheets-Sheet 4 FiledSept. 18, 1964 INVENTOR.

ROBERT L. SJOSTROM ATTORNEYS United States Patent 3,294,395 .SI-IEETFOLDER Robert L. Siiistriirn, Boea Raton, Fla., assignor to SjostrornAutomations, Inc, Boca Raton, Fla., a corporation of Florida Filed Sept.18, 1964, Ser. No. 397,385 7 Claims. (Cl. 270-62) The present inventionrelates to an improved means and method of folding sheets of flexiblematerial and, in particular, to an improved means and method of foldingsheets up to the size of large bedsheets.

It is customary to place a folding mechanism at the end of an ironer incommercial laundries and linen supply plants. These folding mechanismswhich have been used are of substantial size, often up to ten feet inlength. Because of their lengths, such sheet folders have limitedutility and cannot be used with every sheet ironer.

In addition, such sheet folding mechanism have involved and complicatedelectrical and mechanical motions and quite often utilize sophisticatedelectronic circuitry, which often results in frequent breakdowns andfailure of the machines when in constant use.

It is therefore an object of the present invention to provide animproved means and method of folding sheets in which a sheet folder ofrelatively small size may be conveniently located at the end of anyconventional ironer to receive successively fed sheets. A further objectof this invention is to provide a sheet folding mechanism which issimple in design, is not susceptible to frequent breakdown, requireslittle maintenance, and utilizes a very simple folding mechanism havingfew moving parts, and does not require the use of sophisticatedcircuitry including vacuum tubes, transistors or comparable components.A further object of this invention is to provide a compact improvedsheet folder adapted for multiple lane use and which will bypass smallpieces and handle king size sheets as well.

A further object of this invention is to provide an improved compactsheet folding machine in which a plurality of transverse folds areeffected in large sheets by means of folding means including threeadjacent rolls positioned with their axes one above the other. A furtherobject of this invention is to provide a means for effecting successivelateral folds in large sheets in rapid succession with the second foldbeing formed as the first fold is being completed.

In the present invention there is provided a sheet folding machine foreffecting the plurality of lateral folds in sheets that includes meansfor feeding a sheet in a forward direction to a selective position. Apair of means for effecting successive folds in the sheet transverselyof this forward direction are positioned at the end of the feedingmeans. The fold means includes means for eifecting a first fold with afirst force in a direction angular to the forward direction, preferablyrearwardly and downwardly, and means for effecting a second fold belowthe means for eifecting the first fold with the fold being effected by aforce in a direction angular to the first force and preferably in aforward direction. The folding mechanism preferably includes means forautomatically measuring the length of the sheet being folded, and meansfor calculating from this length the precise location to whichsubsequent folds are to be effected. Such measuring and calculatingmeans may be of any suitable type but preferably comprise a meansdisclosed herein.

These and other objects and advantages of the present invention will bemore clearly understood when considered in conjunction with theaccompanying drawings in which:

FIG. 1 is a cross sectional elevation of the sheet folding machine takensubstantially along the line 1-1 of FIG. 3;

FIG. 2 is an end view of the machine shown in FIG. 1 with coveringplates shown in broken outline to expose 3,294,395 Patented Dec. 27,1966 ice drive mechanisms, with FIG. 2 taken substantially along theline 22 of FIG. 3;

FIG. 3 is a front end view of the machine looking from the right of FIG.1;

FIG. 4 is a rear end view of the machine looking from the left of FIG.1;

FIG. 5 is a schematic illustration in enlarged detail of the followingmechanism;

FIG. 6 is a schematic illustration of some of the electrical details ofthe present invention; and,

FIG. 7 is a further schematic of the electrical components of thepresent invention.

In the present invention there is provided a folding mechanism havingside frames 1 and 2. These side frames may comprise a double wall memberinterconnected by webs 3 to form an enclosure adapted to contain variouschain drives, spockets and other components which preferably should beconcealed or covered for safety purposes or for improved machinefunctioning. A plurality of pipe spacers or transverse support means 17extend between side frames 1 and 2 and hold these frames in rigidinterengagement. Suitably journaled between the side frames 1 and 2 is aconveyor system 4 which comprises, preferably, a first conveyor beltmeans 5, a second conveyor belt means 6, and a third conveyor belt means7. Conveyor belt means 5 (FIG. 1) is formed of a pair of rolls 8 andparallelly mounted and supporting a series of belts 10 for movement withtheir upper surfaces 11 in a forward direction.

The first conveyor means 5 has its forward roll 8 suitably journaled atits ends in journals 12 (FIG. 2) in turn secured to the side frames 1and 2. The rearmost roll 9 is journaled in journals 14 with the journals14 in turn secured to elongated frame members 16 and 18. The framemembers 16 and 18 are in turn pivotally supported on the side frames 2and 1, respectively, to permit the first conveyor means 5 to pivot aboutthe axis of roll 8. Chains 20 secured at one end to the frame members 16and 18 are adapted to engage a suitable support on an ironer (not shown)with which the sheet folding means is to be associated. Thus, the uppersurface 11 can be positioned immediately below the delivery rolls orbelts of an ironer to receive sheets as they move from the ironer.

The second conveyor belt means 6 (FIG. 1) comprises a forward roll 22and a rearward roll 24 parallelly mounted and journaled in journals 26and 28 (FIG. 2) in turn secured to the side frames 1 and 2. The rolls 22and 24 carry a plurality of endless belts 30 with the upper surface 32of these belts upwardly inclined preferably at an angle of approximately45. A guide means preferably formed of a plurality of guide figures 34is positioned rearward of the second conveyor belt means 6, andpreferably comprises a cross member 36 supporting a series of paralelarcuate fingers extending arcuately about and in spaced relation to therearward portion of roll 24, to guide sheets moving rearwardly over thebelts 30 toward the third conveyor belt means 7.

The third conveyor belt means 7 comprises a forward roll 38 and arearward roll 40 parallelly mounted in journals 42 and 44 in turnmounted in the frame members 1 and 2. These rolls 38 and 40 carry aplurality of endles belts 46 having upper surface 48. Roll 40 ispositioned preferably below and rearward of roll 24, while roll 38 ispositioned forward of and preferably above rolls 8 and 22. The uppersurface 48 of conveyor belt means 7 is preferably substantially parallelto the upper surface 32 of conveyor belt means 6 and preferably inpartial facing relation with the lower portion of conveyor belts 30.Preferably surface 48 lies at an approximate 45 with the horizontal. Amicroswitch 50 has its actuating finger projecting upwardly betweenadjacent belts 46 in the conveyor belt means 7 for purposes hereinafterdescribed.

The folding mechanism best illustrated in FIG. is located at the forwardend of the machine adjacent the forward end of the third conveyor beltmeans 7. In this arrangement there is provided a first fold means 52 anda second fold means 53. The first fold means includes a roll 54supported on an axis forward of and below the axis of roll 38 with theroll 54 suitably journaled in journals 56, in turn secured to the sideframes 1 and 2. Rolls 38 and 54 have a space 58 formed between -themwhich defines a first line of tangency at which a first fold iseffected. A second line of tangency 60 is formed between roll 54 androll 62, with roll 62 suitably supported by journals 64 with its axisbelow and preferably slightly rearward of the axis of roll 54. Amicroswitch 68 is positioned with its finger directed toward the firstline of tangency 58 and a microswitch 70 is positioned with its fingerdirected toward the second line of tangency 60. An air pipe 72 extendstransversely of the machine between the side frames 1 and 2 and isprovided with a series of perforations aligned with and adapted todirect a force of air towards the first line of tangency 58. A secondair pipe 74 below and rearward of air pipe 72 also extends between sideframes 1 and 2, and is provided with a series of perforations alignedwith and adapted to direct a force of air toward the second line oftangency 60. Preferably, the air pipe 72 is positioned so that its lineof perforation is adapted to direct a force of air downwardly andrearwardly, while air pipe 74 is positioned so that its line ofperforations is adapted to direct a force of air forwardly. A cap 76extends arcuately rearwardly from air pipe 72 over and in spacedrelation to roll 38. A second guide plate 78 is parallel to and has itsrear edge positioned over the upper forward portion of roll 54. Themajor surface of this plate 78 is inclined forwardly and downwardly. Athird guide plate 80 is parallel to and has its rear end substantiallytangential with the forward portion of roll 62. This plate 80 isinclined forwardly and downwardly with its lower portion arcuatelycurved to a position adjacent platform 82. The plates 76, 78 and 80 areall suitably secured at their sides to side frames 1 and 2 with plate 78below and forward of plate 76, and with plate 80 below plate 78. Plate80 has its rear edge rearward of the forward edge of plate 78. Plate 78is adapted to guide sheets passing over roll 54 forwardly and hold themspaced from roll 62. Plate 80 is adapted to guide sheets passing overroll 62 forwardly and downwardly onto platform 82. Platform 82 extendsforwardly of the machine and is suitably secured to the side frames 1and 2 by suitable means which may comprise a pair of rearwardlyextending arms 84 at either side in turn secured to the side frames bybolts or braces 86.

The various conveyor belt means and folding rolls are driven from acommon drive source by a simple means best illustrated in FIG. 2.Sprockets are mounted on the shafts on which rollers 8, 22, 38, 54 and62 are mounted. These sprockets 90, 92, 94, 96 and 98, preferably, alllie in a common plane on the side of a wall member of frame 1 oppositeto the side on which the rollers are positioned. A chain 100 operativelyinterengages each of these sprockets by passing on the outside ofsprockets 90, 94 and 98 and on the inside of sprockets 92 and 96. Thechain is driven by a motor 102 (FIG. 3) having a shaft 104 whichprojects through the wall member of frame 1 and has the sprocket 106mounted on it. A

suitable idler sprocket 108 may be mounted on the wall member of frame 1to take up slack in the chain 100. The chain 100 moves in the directionof the arrows 110, which in turn causes the upper surface 11 of conveyormeans 5 and the upper surface 48 of conveyor means 7 to move in aforward direction and the upper surface 32 of conveyor means 6 to movein a rearward direction. The chain also causes roll 54 to move in acounterclockwise direction and rolls 38 and 62 to move in a clockwisedirection, as viewed in FIG. 5. Actuation of the air blast through pipes72 and 74 are controlled respectively by solenoid valve meansschematically illustrated in FIG. 7 at 112 and 114. These solenoidvalves have actuating coils 116 and 118 which, when energized, will openthe valves to permit air to pass into the tubes 72 and 74 from asuitable source 120. The circuit in which coils 116 and 118 areconnected includes three constant speed motors 121, 122 and 123. Forquarter folding bed sheets, motor 122 effectively operates at twice thespeed of motor 121 and motor 123 effectively operates at twice the speedof motor 122. This speed differentiation may be attained by using motorsof different speeds or by using suitable gear reductions attached to thedrive shaft. Other speed ratios may be used for attaining folds otherthan quarter folds. These motors are connected between the hot line 124and ground line 125 by suitable leads 128 for actuating from thealternating current power source 129. A suitable switch 130 may beprovided for turning on and off the entire circuit. The armatures 121a,122a and 123a respectively of these motors 121, 122 and 123, areconnected respectively to electromagnetic clutches 134, and 136. Theseelectromagnetic clutches are used to selectively engage the brushes 138,139 and 140 of the commutators 141, 142 and 143 respectively with themotors 121, 122 and 123. The brushes 138, 139 and 140 are adapted tocyclically pass over the contacts of the commutators 141, 142 and 143.The commutators 141, 142 and 143 should be substantially identical inconstruction with equal numbers of contacts in each of the commutators.In the preferred embodiment, 56 contacts are provided. For simplicity,five. corresponding contacts, indicated by numerals 1 to 5, incommutators 141, 142 and 143, are shown connected in series by lead 150.For simplicity, only one lead is shown connecting the correspondingcontacts in commutators 142 and 143 but it should be understood thateach corresponding set of the 56 contacts is connected in series. Poweris supplied successively to the contacts of commutator 141 from a DOpower supply by the lead 152 which is carried at one end of the rotor138 to make successive electrical contacts with the contacts of thecommutator 141, and is connected at the other end to the power source129 through a rectifier 153. The lead wire 154 has one end carried bythe rotor 139 for making successive electrical connections with thecontacts of commutator 142. The other end of this lead 154 is connectedto the relay 155. Lead 158 has one end carried by the commutator rotor140 for successive electrical connections with the contacts ofcommutator 143 and the other end is connected to relay 159. The clutch134 is normally open, disengaging the motor 121 and the rotor 138. It isclosed to cause rotor 138 to rotate when the coil 160 is energized. Thiscoil 160 is energized on closing of microswitch 50 from its normallyopen contact 50a to its normally closed contact 501). This microswitch50, when closed, carries power between a hot line and a ground line 125.

Clutch 135, when energized interengages motor 122 and rotor 139 to causeit to move over the contacts at a rate twice the rate of movement ofrotor 138. The actuating of clutch 135 occurs on energization of coil172 which is connected between the hot line 170 and the contact arm ofmicroswitch 68. And when the contact arm of microswitch 68 is closed tocontact 68a, coil 172 will be energized. Clutch 136 is actuated in asimilar fashion to clutch 135. In this arrangement the clutch 136 isactuated bycoil 174 to close the normally open clutch and therebyinterengage the rotor 140 with the constantly rotating motor 123. 'Thecoil 172 is connected between the hot line 170 and the contact blade ofmicroswitch 70 and this coil 174 is energized when the contact blade isclosed to terminal 70a of the microswitch 70.

The relay 155 has a coil 155a, which when energized will cause thecontact blade 155b of the relay to move from its normal position incontact with contact 1550 to contact 155d. Relay 159 has a similarconstruction with a relay coil 159a adapted when energized to causemovement of the contact blade 15912 from a normal position in engagementwith contact 1590 to engagement with contact 159d. Contact 1590 isconnected to ground line 125. Contact 1550' is connected to line 172a.Contact 155d and contact 159d are respectively connected to contacts180a and 181a respectively of the switch 180 and 181 and respectivelywithin the relay assemblies 155 and 159. The contact blades 18Gb and181b ares respectively connected through lead wires 182 and 184 to thecoils 116 and 118 of the solenoid valves 112 and 114 for actuatingthereof. The contact blades 18% and 181k are controlled respectively byenergization of the relay coils 155a and 159a so that these contactblades close respectively to the contacts 180a and 181a uponenergization of the coils 155a and 159a.

The circuit operates in conjunction with the other mechanism as follows:When a sheet passing through the machine engines microswitoh 50, themicroswitch blade is closed against contact 5% to energize coil 160,thereby interengaging the running motor 121 and rotor 138. The rotor 138then moves successively over contacts in the commutator 141 and stopsafter the trailing edge of the sheet has passed microswitch 50 and hasthere-by allowed the switch to open and the coil 160 to be deenergized.For purposes of this example, assume that the rotor 138 reaches andstops at contact 3 in commutator 141, as illustrated in FIG. 7, afterthe trailing edge of the sheet has passed. The sheet continues to moveover the belt means 7. When the lea-ding edge of the sheeet is carriedby belts 46 of the belt means 7 over roll 38, it then engagesm-icroswitch 68. When microswitch 68 is engaged its blade closes tocont-act 68a, thereby energizing coil 172, causing rotor 139 to turnwhen the clutch 135 closes. Since motor 122 is a constant speed motorthat rotates at twice the speed of motor 121, the rotor 139 will reachcontact 3 in commutator 142 in half the time that rotor 138 reachedcorresponding contact 3 in commutator 141 from a corresponding startingposition. When rotor 139 reaches contact 3 in commutator 142, the sheetwhich has closed microswitch 68 should be positioned so that itstransverse center line is positioned between air tube 72 and the line oftangency 59 (see FIG. 5). At that instant power is passed through lead152, the series connected contacts 3 of the commutators 141 and 142,lead 154, relay coil 155a contact blade 155b, contact 1550, and groundline 125 through closed switch 68. However, upon energization of coil155a, contact blade 15512 is closed from contact 1550 to contact 155a,and at the same time blade 180 h closes to contact 180a, therebyenergizing coil 116 to open the valve 112 and emit an air blast throughtube 72. The air blast will remain on until the sheet moves fromengagement with microswitch 68. This will occur quite quickly since theair blast blows the sheet at its center line away from this microswitch,as can be seen from the arrangement in FIG. 5.

A similar action occurs after the once-folded sheet drops down and itsleading (now folded) edge engages microswitch 70. When microswitch 70 isengaged, coil 174 is energized to close the clutch 136 and cause therotor 140 to rotate from a position corresponding with the initialposition of the other rotors at a speed twice tact blade 15% is movedfrom contact 1590 to the contact 159d to energize the coil 118 throughthe correspondingly moved contact blade 181b and line 184. When coil 118is energized, the valve 114 is open emitting and air blast through tube74 at a point halfway between the leading and trailing edges of theonce-folded sheet. This air blast from tube 74 causes the once-foldedsheet to move between rolls 62 and 54 at the line of tangency 60,thereby folding it once more into a quarter folded arrangement. Themovement of the sheet away from microswitch 70 opens microswitch 70 andcauses coil 174 to be deenergized.

Having now described my invention, I claim:

1. A sheet-folding machine comprising a frame having opposed sidemembers,

means for forwardly feeding a sheet including parallel rear and forwardrolls with endless conveyor belt means supported on and rotated by saidrear and forward rolls,

means journalling said rear and forward rolls in fixed relation to saidframe with the axis of said forward roll above the axis of said rearroll whereby the upper surface of said belt means is inclined upwardlyfrom the rear to the forward end of said machine,

means for effecting at least one lateral fold in a sheet moving fromsaid upper surface of said belt means at the forward end thereofincluding a pair of parallel adjacent fold rolls. means journalling saidfold rolls in fixed relation to said frame with the axis of one foldroll positioned rearwardly of and below the axis of the other of saidfold rolls whereby the angle formed between a plane through the axis ofsaid rear and forward rolls and a plane through the axis of said foldrolls is acute,

means for forcing a sheet passing adjacent said fold rolls between saidfold rolls whereby said sheet is folded along a transverse lineintermediate the forward and rear ends of the said sheet, and

means for rotating all of said rolls whereby said upper surface of saidbelt means moves forwardly and said folding rolls rotate in oppositedirections.

2. A sheet-folding machine as set forth in claim 1 wherein said otherfold roll is positioned adjacent said forward roll with its axis belowand forward of the axis of said forward roll, and means for forcing asheet passing from said upper surface of said sheet-folding machinebetween said forward roll and other fold roll whereby said sheet isfolded along a transverse line intermediate the forward and rear ends ofthe said sheet.

3. A sheet-folding machine as set forth in claim 2 wherein said meansfor forcing a sheet between said fold rolls and said means for forcing asheet between said forward roll and said other fold roll each compriseair-blast means extending parallel to and with air-emitting aperturesdirected toward said rolls.

4. A sheet-folding machine comprising a frame having opposed sidemembers,

means for forwardly feeding a sheet including parallel rear and forwardrolls with endless conveyor belt means supported on and rotated by saidrear and forward rolls,

means journalling said rear and forward rolls in fixed relation to saidframe with the axis of said forward roll above the axis of said rearroll whereby the upper surface of said belt means is inclined upwardlyfrom the rear to the forward end of said machine,

means for effecting at least one lateral fold in a sheet moving fromsaid upper surface of said belt means at the forward end thereofincluding a pair of parallel adjacent fold rolls,

means journalling said fold rolls in fixed relation to said frame withthe axis of one fold roll positioned below the axis of the other of saidfold rolls whereby the angle formed between a plane through the axis ofsaid rear and forward rolls and a plane through the axis of said foldrolls is acute,

means for forcing a sheet passing adjacent said fold rolls between saidfold rolls whereby said sheet is folded along a transverse lineintermediate the forward and rear ends of the said sheet,

means for rotating all of said rolls whereby said upper surface of saidbelt means moves forwardly and said folding rolls rotate in oppositedirections,

a second conveyor means including an upper rear roll, means supportingsaid upper rear roll with its axis parallel to, above and forward ofsaid rear roll,

an upper forward roll means supporting said upper forward roll with itsaxis parallel to, below and rearward of said forward roll,

upper conveyor belt means supported on and rotated by said upper, rearand forward rolls with a lower surface of said upper conveyor belt meansfacing and parallel to said upper surface of said belt means,

and means for rotating said upper conveyor belt means in a directionopposite to the direction of said endless conveyor belt means.

5. A sheet-folding means as set forth in claim 4 having rotatable shaftsprojecting through said side members and mounting each of said rolls,

sprockets mounted on said shafts on the side of a side member oppositesaid rolls,

common endless chain means positioned on the side of said frame oppositesaid rolls and operatively engaging said sprockets, and

means for driving said endless chain.

6. A sheet-folding machine comprising a frame having opposed sidemembers,

means for forwardly feeding a sheet including parallel, rear and forwardrolls with endless conveyor belt means supported on and rotated by saidrear and forward rolls,

means journalling said rear and forward rolls in fixed relation to saidframe with the axis of said forward roll above the axis of said rearroll whereby the upper surface of said belt means is inclined upwardlyfrom the rear to the forward end of said machine,

a second conveyor means including an upper rear roll and an upperforward roll,

means supporting said rolls with their axes parallel to said forward andrear rolls,

upper conveyor belt means supported on and rotated by said upper rearand upper forward rolls with a lower surface of said upper conveyor beltmeans facing and parallel to said upper surface of said belt means,

receiving conveyor means at the rear end of said machine comprising apair of side frames, means pivotally securing said side frames to saidside members, a pair of rolls, means journalling said pair of rolls withtheir axes spaced and parallel to the axes of said other rolls and withone of said pair positioned close to said upper conveyor belt means,said other roll of said pair being remote from said upper conveyor belt,belt means encircling said pair of rolls, and having an upper surfaceadapted to be pivoted over an arc with pivoting movement of said sideframes, means for rotating the upper surfaces of said belt meansencircling said pair of rolls and said upper surface of said belt meansof said endless conveyor belt means in a forward direction and saidupper surface of said belt means of said upper conveyor belt means in arearward direction, and folding means at the forward end of said endlessconveyor means for effecting transverse folds in sheets delivered fromthe forward end of said endless conveyor means. 7. A sheet-foldingmachine as set forth in claim 6 wherein said folding means comprises,

means for effecting at least one lateral fold in a sheet moving fromsaid upper surface of said belt means at the forward end thereofincluding a pair of parallel adjacent fold rolls. means journalling saidfold rolls in fixed relation to said frame with the axis of one foldroll positioned below the axis of the other of said fold rolls wherebythe angle formed between a plane through the axis of said rear andforward rolls and a plane through the axis of said fold rolls is acute,means for forcing a sheet passing adjacent said fold rolls between saidfold rolls whereby said sheet is folded along a transverse lineintermediate the forward and rear ends of the said sheet, and means forrotating said fold rolls in opposite directions.

References Cited by the Examiner UNITED STATES PATENTS EUGENE R.CAPOZIO, Primary Examiner.

1. A SHEET-FOLDING MACHINE COMPRISING A FRAME HAVING OPPOSED SIDEMEMBERS, MEANS FOR FORWARDLY FEEDING A SHEET INCLUDING PARALLEL REAR ANDFORWARD ROLLS WITH ENDLESS CONVEYOR BELT MEANS SUPPORTED ON SAID ROTATEDBY SAID REAR AND FORWARD ROLLS, MEANS JOURNALLING SAID REAR AND FORWARDROLLS IN FIXED RELATIVE TO SAID FRAME WITH THE AXIS OF SAID FORWARD ROLLABOVE THE AXIS OF SAID REAR ROLL WHEREBY THE UPPER SURFACE OF SAID BELTMEANS IS INCLINED UPWARDLY FROM THE REAR TO THE FORWARD END OF SAIDMACHINE, MEANS FOR EFFECTING AT LEAST ONE LATERAL FOLD IN A SHEET MOVINGFROM SAID UPPER SURFACE OF SAID BELT MEANS AT THE FORWARD END THEREOFINCLUDING A PAIR OF PARALLAL ADJACENT FOLDS ROLLS. MEANS JOURNALLINGSAID FOLD ROLLS IN FIXED RELATION TO SAID FRAME WITH THE AXIS OF ONEFOLD ROLL POSITIONED REARWARDLY OF AND BELOW THE AXIS OF THE OTHER OFSAID FOLD ROLLS WHEREBY THE ANGLE FORMED BETWEEN A PLANE THROUGH THEAXIS OF SAID REAR AND FORWARD ROLLS AND A PLANE THROUGH THE AXIS OF SAIDFOLD ROLLS IS ACUTE, MEANS FOR FORCING A SHEET PASSING ADJACENT SAIDFOLD ROLLS BETWEEN SAID FOLD ROLLS WHEREBY SAID SHEET IS FOLDED ALONG ATRANSVERSE LINE INTERMEDIATE THE FORWARD AND REAR END OF THE SHEET, ANDMEANS FOR ROTATING ALL OF SAID ROLLS WHEREBY SAID UPPER SURFACE OF SAIDBELT MEANS MOVES FORWARDLY AND SAID FOLDING ROLLS ROTATE IN OPPOSITEDIRECTIONS.